I've used these beads between both cobalt roundels and cobalt cubes and even black matte beads because their size allows for larger beads to slide around over them or to add exquisite beauty to the beads--either matte or glossy--they separate. I will order them again and again to use even with non-blues because the gilding accentuates whatever you may be working with. Right now I am beading a bracelet using these as spacers between two cobalt cubes and between two cobalt roundels in a repeated pattern with no focal bead, using stretch wire without a clasp. Some of my favorite pieces are emphasized with these marbles. And the 8/0 size allows for larger wire work, not always the case with spacers.